BODI bodies of water produce and consume oxygen. It obtains oxygen from the atmosphere and plants as a result of photosynthesis. For flowing water would dissolve more oxygen due to the effect of its agitated and continuous movement. Wastewater containing organic materials is decomposed by microorganisms that utilize the oxygen within the stream. Biochemical oxygen demand (BOD) is the amount of oxygen consumed in this process. Other sources of oxygen-consuming waste include stormwater runoff from agricultural areas or septic systems. In this aspect, oxygen is measured in its dissolved form (DO). If more oxygen were consumed than produced, it would affect the ecosystem supported by the stream or relocate its oxygen-consuming inhabitants to lower profile water bodies. According to APHA, 1992 in their study "Standard Methods for Testing Water and Wastewater" DO levels fluctuate throughout the day and are affected by temperature and altitude. The study also states that cold water has a greater oxygen-holding capacity than warmer water. Water at 0°C had a DO level of 14.60 mg/l compared to water at a temperature of 36°C with a value of 6.82 mg/l. Similarly, in March 1997, at the Department of Natural Resources of the University of Rhode Island, it was highlighted that salinity, altitude, groundwater inflow and water temperature are some of the factors that influence dissolved oxygen in a body of water. The higher the salinity of the water, the lower the amount of dissolved oxygen. Hot water normally contains less oxygen in solution than cold water. Thermal stratification (heating through different layers) causes DO to deplete and eventually completely depletes the levels because there is no replenishment. According to an article by Simpson (1991), ... half of the paper ... dichromated, in acidic conditions. A known excess amount of this oxidant is added to the sample and once the process is complete, the COD concentration value is calculated by measuring the remaining amount of oxidant in the solution. This process is usually performed by titration using an indicator solution. It is measured in milligrams per liter and indicates the mass of oxygen consumed per liter of solution. While the biochemical oxygen demand (BOD) test takes 5 days, the COD test only takes about 2-3 hours for complete completion and analysis. Within this test, all organic contaminants present in the wastewater sample are measured, including non-biodegradable ones. For BOD testing, toxic compounds such as heavy metals cannot be analyzed, so COD testing can be used to measure the concentration of waste that is too toxic for BOD testing.